Post processing of iris images to increase image quality

Abstract

A rapid iris acquisition, tracking, and imaging system can be used at longer standoff distances and over larger capture volumes, without the active cooperation of subjects. Light illuminates the subjects' eyes and a high resolution camera captures images of the irises. The images of the irises are processed by a post processing module to improve their quality. In one approach, the point spread function of the image capture subsystem is estimated using glint reflections from the eye, and the estimated point spread function is used in deconvolution to increase the resolution of the iris images. The post processed iris images have sufficient resolution to be used for biometric identification.

Description

CROSS-REFERENCE TO RELATED APPLICATION(S)[0001]This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application Ser. No. 60 / 803,006, filed May 23, 2006, which is a continuation-in-part of U.S. patent application Ser. No. 11 / 297,578, filed on Dec. 7, 2005, entitled “Iris Imaging Using Reflection From The Eye,” which claims priority under 35 U.S.C. §119(e) to both U.S. Provisional Patent Application Ser. No. 60 / 654,638, “Biometric Identification and Iris Imaging Using Retinal Retro-Reflection,” filed Feb. 17, 2005, and U.S. Provisional Patent Application Ser. No. 60 / 634,331, “Adaptive Optics (AO) Imaging Applied to Biometric Identification Using Iris Imaging,” filed Dec. 7, 2004. The subject matter of all of the foregoing is incorporated herein by reference in their entirety.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]This invention relates to imaging of the human iris, as may be used for biometric identification. More specifically, ...

AI Technical Summary

Benefits of technology

"The present invention relates to iris imaging systems that use post-processing to improve the quality of captured iris images. The system captures lower resolution images and an image post processing module increases the resolution of the images. The system uses light illuminates the subjects' eyes and reflection from the eyes to steer the camera to the eyes and capture images of the iris. The post processing module estimates the point spread function and uses it to reverse the blurring effect. The system can also use multiple images of an iris to improve the resolution of the final post-processed image. The image capture subsystem includes a camera, light source, and fine tracking system that can acquire iris images even without the subject's active cooperation. The acquisition subsystem identifies the approximate location of subjects within a capture volume and the image capture subsystem slews from one subject to the next to acquire images of their irises. The invention provides a solution for improving the quality of captured iris images for biometric identification."

Problems solved by technology

The image capture subsystem captures images of irises, possibly with resolution that is not sufficient for biometric identification.

Images